Maybe one day this urban myth will be put to rest. Lots of reloaders shoot tons of lead bullets in their polygonal barrels... Glocks, HKs, etc. BTW, brand doesn't matter; a polygonal bore is a polygonal bore is a polygonal bore...
Yes, you have to pay attention to ensure you have no excessive lead build-up. This is easily controlled by a knowledgable reloader and simply dealt with if it DOES occur... just run a brush through the bore a few times every 150 rounds or so. I have shot many thousands of cast lead bullets through a variety of HKs and two Glock 19s, with absolutely zero ill effects.
As to accuracy, dunno. All my HKs are phenomenally accurate (when I do my part), but I'm not so sure if that is due to HK's increased quality control/precision manufacturing more than the polygonally rifled bore. One real tell-tale is that you rarely see a drag mark on a fired case out of an HK. This means that the piece is timed properly and the barrel isn't unlocking prematurely. Happiness through better manufacturing...
One other, not-so-well-known characteristic of polygonal bores is that they make forensically identifying bullets shot out of one rather difficult. It can be done if all the planets line up, but not often. Some manufacturers actually offer a special, unique process (for an extra fee, of course) that solves this issue. That said... don't make the mistake of thinking you can smoke someone with your Glock and you're home free. There are other ways of determing what was shot out of which gun... :wink:
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